IP Accounting on 3750 Switches

[Muhammad Arshad]

Hi,

I have 3750 switches installed as my core switch. There are 4 switched stacked all together. we have configured VRF having my communication links terminated here.

I am not able to use IP accounting command. After searching on net, it become clear that IP accounting can not be used with 3750 switches.

Is there any work around to see what are the IP addresses causing high traffic on my communciation links terminated at 3750 switch (VRF) Thanks.

[Leo Laohoo]

Multiple ways to do this ...

First you need to determine which interface is causing high traffic.  The fastest way to see this, in real time, is to use the command "sh controll util".  The ports with no traffic will be "0" and this is expressed in percentage (%). 

Next, once you've identified which interface or interfaces, and you want to determine which IP address, you enable IP device tracking using the following commands:

conf t

ip device tracking

interface

ip device tracking max 10

end

Wait for 15 seconds and then issue the command "sh ip device tracking max 10" and it will show you the entire list.  If you want to filter down to a specific interface then you can use the command "sh ip device tracking interface ".

[Muhammad Arshad]

Dear Leo,

Thanks a lot for your kind support.

[Muhammad Arshad]

Hi Leo,

I tried above mentioned command but all ports shows "0" traffic. Actually I am using VRF configuration on this core switch. VLAN 300 is the member of VRF. MRTG of service provder shows that there is a traffic on this link. How can identify IP addresses passing on this link. Thanks

[Leo Laohoo]

I tried above mentioned command but all ports shows "0" traffic. 

Ok, this means that at the time when the command was entered there was no traffic.  Zero percent. 

How about this:  Clear all the counters to all access ports (do not clear the counters to your uplinks).  Wait for 24 hours and find out which one is the highest.   Then run the commands in my first post.

[Muhammad Arshad]

Ok Thanks... I will do same.

[Leo Laohoo]

Do that.  I'm going to sleep. 

[TCSe Noc]

Dear Leo,

This command is not helping to understand the traffic or the top talkers. And 3750 is not supporting netflow also.